Sanderson is a Marine turned Warlock Class Guardian. He was chosen by Equestria Supreme Co-Ruler Princess Celestia and Zordon, a wise sage from the world Eltar, to find the lost guardians and restore balance to the Multi-Universe.
Sanderson tends to become confused at strange occurences, but quickly gets used to them. He's looked up to as a leader of a Marine Squad before the events of the storyline. He was chosen by Zordon due to his strength and observation skills, as well as his motiviation to get his missions done successfully and that he deeply cares for his teammates and friends.